Disclosed in Japanese Patent Laid-open Publication 1 (2011-142859) is a brush cutter comprising a frame rod, a cutter head provided within a front end of the frame rod and a controller head provided in a rear end of the frame rod. The cutter head of the brush cutter includes a front housing fixed to the front end of the frame rod, an electric motor mounted within the front housing, a rotary shaft supported within the front housing to be driven by the electric motor, and a cutting blade mounted to the rotary shaft. The controller head includes a rear housing fixed to the rear end of the frame rod and a controller contained in the rear housing. In the brush cutter, a battery pack is detachably mounted within the rear housing.
In the brush cutter, a single battery pack contained within the rear housing is in general in the form of a large size battery pack of high voltage (for instance, 36 volt) for activating the electric motor of high power. Such a large size battery pack of high voltage may not be used as a source of power supply for other work apparatus such as electric power tools. For this reason, the large size battery pack is adapted for use only in the brush cutter in spite of expensive. An object of the present invention is to provide a brush cutter without use of the expensive large size battery.